Northern Songliao Basin, Young Reservoir, Petroleum System

Based on studying the structure, sedimentation, thermodynamic, geologic stress and hydrodynamics background in the north of Songliao basin, this paper studied and evaluated the sourcerock conditions, reservoir conditions, caprock conditions, trap conditions and migration and accumulation conditions of F, Y oil layers. Based on these, this paper studied deeply the main factors controlling accumulation and distribution of oil or gas and accumution models through studying types of oil or gas reservoirs and oil or gas distribution laws of F, Y oil layers in the north of Songliao Basin. This paper pointed out sourcerocks, caprocks, faults and hydrodynamics power to be the main factors controlling oil or gas accumulation and distribution. There are-two models of oil or gas accumulating in fault-lithology or fault block traps through migrating downward under the regional caprock and oil or gas from sourcerock downward accumulating in fault-lithology or fault block traps in reservoirs upward by migrating through faults. According to separating touch of fluid potential field in F, Y oil layer, eight oil or gas accumulation systems are divided in F, Y oil layer, they are Daqing-Zhaoyuan oil or gas accumulation system, Longhupao-Taikang oil or gas accumulation system, Heiyupao-yian oil or gas accumulation system, Haerbin-Shuangcheng oil or gas accumulation system, Zhaodong-Mingshui oil or gas accumulation system and Hailun oil or gas accumulation system. According to oil or gas accumulation conditions,this paper considered Daqing -Zhaoyuan, Yingtai-Daan, Longhupao-Taikang and Chaoyanggou-Zhaodong oil or gas accumulation systems are best, Zhaodong-mingshui oil or gas accumulation system is better, Haerbin-Shuangcheng, Hailun and Qiqihaer-Yian oil or gas accumulation systems are middle. Therefore, Qijiagulong sag, Daqing placanticline, Sanzhao sag and Chaochang area are favorable areas to find the accumulation of oil or gas from sourcerock of Qingshankou formation. Sanzhao sag, Gulong sag, Qijia sag and Heiyupao sag to be favorable area to find the accumulation of gas from sourcerock deep.